MINUTE ANATOMY OF THE PAPILLAE OF THE FEOG’S TONGUE. 
445 
The structures entering into the formation of the papilla are the following : — 
1. The connective tissue which forms the body of the papilla. 
2. The “ epithelium.” 
3. The nerve-fibres in the body of the papilla, and the fibres prolonged from them 
which form a plexus upon its summit. 
4. Nerve-fibres ramifying in the connective tissue, upon the capillary vessels and 
amongst the muscular fibres. 
5. The muscular fibres. 
6. The vessels. 
The Connective Tissue. 
The nerves, vessels, and muscular fibres are imbedded in a very transparent basis- 
substance which exhibits a slightly striated or fibrous appearance when stretched, 
but this structure in all the papillae of the Hyla is exceedingly delicate and trans- 
parent. 
The great majority of the nuclei seen in this basis or connective substance are 
undoubtedly connected with the nerves, vessels, and muscular fibres, but there are a 
few which seem to belong to the connective substance alone, and may therefore be 
called “ connective-tissue corpuscles .” It is possible that these at an earlier period may 
have been connected with nerves or muscles ; they have descended from the same nuclei 
or masses of germinal matter as the nuclei taking part in the production of these 
tissues. 
I consider that indefinite connective tissue of this kind results principally from the 
accumulation of the remains of higher structures, especially nerve-fibres, which were in 
a state of functional activity at an earlier period of life. At an early period of deve- 
lopment nuclei (masses of germinal matter) can alone be detected. As development 
proceeds, tissue is formed by these nuclei, and increases as age advances. The large 
and fully-formed fungiform papillae have twice as many nerve-fibres as smaller and 
younger ones. During the development of such an organ as one of these papillae many 
changes occur, and much texture is produced and removed before the papilla attains 
its fully developed state. That passive substance called connective tissue which remains 
and occupies the intervals between the higher tissues, which possess active and special 
endowments, slowly accumulates, but undergoes condensation as the organ advances in 
age. Amongst this are a few nuclei which can no longer produce anything but inde- 
finite “connective tissue” of the same character. In Plate XXI. fig. 9 it would have 
been impossible, had the specimen been prepared in the usual manner, to have deter- 
mined if the nuclei marked a, h were nuclei of the muscle concerned in producing 
muscle, or connective-tissue corpuscles concerned in the formation of connective tissue 
only. This question requires restudy from a new point of view. It is quite certain that 
many of the nuclei figured in all my drawings in connexion with nerves , vessels, muscles, 
and other tissues, would, if the specimens had been prepared in a different manner, so 
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